tDCS has come up before many times. Did you search the site and read previous comments?

It's a reference to 'em cities', where the limiting resource will be a combination of electricity generation + cooling. Scandinava has dams and geothermal energy so cheap electricity (think why Iceland has aluminum smelters) but also cold weather and even colder oceans, so cheap cooling.

Sure. But I'd point out that this observation (that you can hedge) cuts against Soylent as well: while consuming regular food to limit your downside from deficiencies in Soylent should work for overprovisioned substances, you're also limiting your upside since the more regular food you consume the less Soylent you must be consuming.

I look forward to your self-experiments...

Factors why I have not and probably will not:

1. Soylent costs more than my current diet, limiting gains
2. it is a priori highly likely to fail since we know for a fact that severe nutrition deficiencies can be due to subtle & misunderstood factors (see: the forgetting of scurvy cures) and that nutrition is one of the least reliable scientific areas
3. his work is even more likely than that to have problems because he hasn't consulted the existing work on food replacements (yes, it's a thing; how exactly do you think people in comas or with broken jaws get fed?)
4. given #2, the negative effects are likely to be subtle and long-term means that on basic statistical power grounds, you'll want long and well-powered self-experiments to go from 'crappy self-experiment' to 'good self-experiment'*
5. given the low odds of success (#2-3), the expensive powerful self-experiments necessary to shift our original expectations substantially due to long-term effects and subtlety (#4), and the small benefits (#1), the VoI is low here
6. my other self-experiments, in progress and planned, suffer from many fewer of Soylent's defects, hence have reasonable VoIs (Specifically: I am or will be investigating Noopept, melatonin, magnesium l-threonate, coluracetam, meditation, Redshift, and lithium.)
7. VoI current/planned self-experiments (#6) > VoI Soylent cloning/tweaking (#5)
8. hence, the opportunity cost of Soylent is higher than not, so I will continue my existing plans

* although see my reply to Qiaochu, at this point Rob isn't even at the 'crappy' level

Of course blocking on weeks wouldn't rule out long-term side-effects. (Nothing would, short of a multi-decade RCT to investigate all-cause mortality.)

My point was that he hasn't even done that much. Yet, he is happy to blog about the 1 week he took off Soylent to fly to LA and how crappy he felt wandering around a strange city and how this proves normal food sucks...

To copy over my earlier G+ comment:

ಠ_ಠ I completely disapprove of this. Soylent is a fun idea, sure, but Rhinehart's asking for $100k to launch a Soylent manufacturing company?! He hasn't even done even the minimal crappy self-experiments he could've done very easily, like randomize weeks on and off Soylent! Nor, AFAIK, has he published any of the results from the early volunteers or anything, really. This is ridiculous.

See also Hacker News

1. http://dl.dropboxusercontent.com/u/85192141/1996-walberg-olympiadcollection.pdf
2. http://dl.dropboxusercontent.com/u/85192141/2004-nokelainen.pdf
3. couldn't get it through UWash, sorry.

Thanks.

I failed to get this through the UWash e-journals.